Vacuum pump



Feb. 8, 1938. 1 M, DOUGHERTY 2,107,889

VACUUM PUMP Fired June 26, 1935 y Patented Feb. 8, 1938 lo `mejApiil 30,1935, and some elements embodied *inthe structure of the :present 'invention are de- The y`1i 'rior art structi'lresV referredetofutilizeja n at in th'e condensingtankjfor controlling the l5 li'a. 'din'ittanceY^ of steam thereto intermittently` 'f 'Iv'he object of the present invention 4is to in crease the eiiiciency of the device by making the same more quickly responsive to changes inthe waterlylevel ifrrthe Acondensing tank.' Briefly, this "20 g'enerallobject is attained lbyV controlling the steam inlet valve-with va thermostat exposed a1- 1 ternatelytosteam direct from the boiler 'and to f water direct from the return system, which is usually 30 tov 40 cooler!l than thesteam. The

. .thermostat is operatively'connected to a steam jvalvefandpreferablyanjair valvefalso,r to conf. trelrthepassa'ge of iiuids-*to and vfrom thetank. f HlfOthe'r detail objects of the'inventionand the y Vmeans for vattaining thefsame will be apparent -3'0 from/the following description, reference being had tothe accompanying drawing in which-r l Fyigure lis a verticalsection throughthe conn f Vdensingt'ank*and some of theapparatus associvated therewith, other V`portions of the'apparatus 535 vibeingf'indicated in 'elevation `andsome electrical re'quipniei'it beingy shown'diagrarnmaticallyfV `i Rigure 2 isa corresponding section through f ysomelof'the parts shown in' Figure v1 but showing' the same ina different operating position.r

l The lcondenser tank'is indicated at I and is l'nlovidedr with a 'series' of, airues y2 extending v-le'n-gthwise,through the same.' A blower 3 at one 'elldof the tank ,is operatedby a motor 4 to draw 'ain through the' ues :and discharge the same 5 ingftobe heated. Thefsteam pipe 6 leads vfrom "the boilerjand hasbranches 6a and 6b. .l The rev turn pipe V'I leads 'from the heatingv system direct V315Uv-tothe boiler water supply vpipe 8. A lateral 9 leads frompipe I tothe upper portion of tank QI. to admit water tothe tank. A discharge pipe Ill leads fromthelower portion ofthe tank back tothe boiler supply line 8'. Check valves I I, I2,

` ,55 I3, fendu iprevent the ow'of. `Water kthrough PATENT OFFICE VACUUM PUMP 'Jphn M; Dougherty, Y St: Louis, Mq. Appuation June lzs, 1935, Y serial No. 28,465 l1o claims. (c1.'1in- 252)A these pipes in directions opposite to the arrows adjacent the Valves.

AllV of the above mentioned parts vare well known and in themselves do not constitute the present invention. n 5 -A'therniostatic device I5 includes an element I6, .extending substantially the full depth of the tank, and parts associatedtherewith arranged toraise and lower the plunger I'I which is connectedito a lever I8 pivoted at I9 and mounting 10 a mercury switchen. A spring ZI tends' tohold lever I8 in thep'osition shown in Figure iin whichA switch 20 is in' position'to open the electricv circuit controlled thereby. A steam inlet valveg 22 controls the passage of steam from 15 branch 6a through pipe 23 to the interior of 'the tank.v A spring 24 tends to raise the valve vdisc 25 from its Yseat and a solenoid 26, whenv energized, closes. the valve against the tension of spring'24. "20 .Pre'ferably the steam inlet and the thermostatic element I6 are located near opposite ends of the tank.

A'pipe 21 leads from the interior of the tank to an Vair relief valve 28, the disc'29'of which is 25 normally raised fromiits seat byaspringv 30. A solenoid 23|, when energized, rmoves disc 29 against its seat, overcoming the tension of spring 30. Solenoidsw26 and 3I are energized through a "single circuit which is closed by switch 29 when 30 'first steam generated by the boiler will be led directly through pipe 6a and valve 22 into the tank at the end opposite the air 'relief pipe 2'I. The steamwill force 'a substantial portion of the air 45 out through valve 28 and will heat thermostatic element I6 until element I'I moves upwardly, shifting mercury switch 20 and closing the circuit which energizes solenoids 26 and 3I, whereupon valves 22 and 28 close and the admittance 50 of steam to the tank is interrupted. The cool air surrounding the tank and passing through ues 2 condenses the steam, creating a partial vacuum in the tank and drawing water into the ltankthr'ough pipe 9. Since the end of pipe 9 is `55 to shift switch 20 in the opposite direction, opening the circuit and permitting springs 24 and 30 to open valves 22 and 28 admitting an additional quantity of steam which heats the thermostatic element I6 and the cycle of operations is repeated so' long as the system is in operation. After a' substantial amount of Water has been drawn into thetank, subsequent admission of steam results in the discharge of Water through valve i4 and pipe l0 to the boiler return pipe 8.v

Any tendency of water to escape, under steamr pressure, through air relief pipe 2l and valve 28 will result in the immediate closure of the Valve passage by afloat 38 which normallyv rests on projections .at thebase of the valve and is not aifected by .the passage ofair through the valve and has no function except as ljust described.

If the water should' rush into the tank Vfaster than the thermostat controlled mechanism can function to open steam valve 22, oat 312 will be raised and steam valve 3l will be opened and the pressure thereby set up in the tank will terminate the inflow of water. l y

I'he current of'v air inducediby blower 3 `not only serves .to provide a space heater'rbut' also accelerates the condensing action occurring inthe tank. The circuit for motor 4 is controlled by the hand operated switch S only and the action of the blower is continuous and not intermittent `as vis the device controlled by switch 2U.

'I'he 'structure described is illustrative only andv the details of the structure and assembly mayA be substantially varied `without departing from the spirit of the invention. Y Obviously suitable linkages could be provided between the thermostat and valves 22 and 30 to operate the valves, or the valves could be motorized and controlled by electric switch similar to that shown. The emergency oat controlled steam inlet may be unnecessary `in some installations and can be omitted. I contemplate the exclusiveuse of these and all other modifications of the invention coming within the scope of my claims.

I claim: A

1. In a structure of the class described, a condensing tank, means for admitting water to said tank and for discharging water therefrom, a .Valve for admitting steam to said tank, a thermostat constructed and arranged for contact by the air, steam, and water in said tank, and an electromagnet and springmechanism controlled by said thermostat to open said valve when said thermostat is cooled and to close said valve when said thermostat is heated, a float, operable 'by the water in said tank, and means actuated by said float when the water in said tank reaches an abnormally high level, toadmitsteam to said tank independently of said thermostat.

2. In a structure of the class described,a condensing tank, means for admitting water to said tank and for discharging water therefrom, a valve for admitting steam to said tank, a thermostat device including an element arranged for successive contacts by relatively small quantities of steam and water in said tank andelectromagnet and spring means controlled by said device and operatively connected to said valve to respective- 1y close and open the latter when exposed to steam and Water in said tank, a float, operable by the water in sai-d tank, and means actuated by said float when the water in said tank reaches f an abnormally high level, to' admit steam to said tank independently of said thermostat. Y

3. In a structure of the class described, a condensing tank, means for admitting Water to said tank and for discharging water therefrom, a valve for admitting steam to said tank, a thermostat including an element in the lower portion of said tank, and electromagnet and spring means controlled by said thermostat operatively connected to said valve to open the same when said element is exposed to water or cool air in said tank and to close said valve when said element isexposed to steam in said tank, a oat, operable bythe water in' said tank, and means actuated by said float when the water in said tank reachesan abnormally high level, to admit steam to said tank independently of said thermostzett.v

4. In a structureof the class described, a condensing tank, means for admitting Water to said tank and for discharging water therefrom, a valve for admitting steam to said tank, a thermostat device having an element in said tank exposed to vsteam present in said tank and to water present in the lower portion of said tank, electromagnet means controlled by said device when said element is cooled by water admitted to said tank, to open said valve, and means controlled by saiddevice, when said element is heated by steamadmitted by said valve, to close said valve, a float, operable by the water in said tank, and means actuated by .said oat when the water in said tank reaches an abnormally high level, to admit `steam to said tank independently of said thermostat. I y

5. In a structure of the class described, a condensing tank, means for admitting water: to said tank and for discharging Water therefrom, a

Valve for admitting steam to said tank, a thermostat extending into said tank and having an velement shifted to different positions when said thermostat is heated and cooled, an electric circuit having a rswitch openedand closed by shifting of said element, andan electromagnet Vin said circuit for controlling said valve, a float, operable by the Water in said tank, and means actuated by said fioat when the water in said tank reaches anabnormally high level, to admit steam to said tank independently of said thermostat. y 6. In a structure of the class describeda condensing tank, means for admitting water to said tank and for discharging water therefrom, a valve for admitting steam to said tank, a thermostat extending into said tank and having an element shifted to different positions when said thermostat is heated and cooled, an electric circuit having a switchV closed by saidelement when heated, an electromagnet energized by'said circuit when closed to open said valve, and a spring for opening said valve when said element is heated to open said switch, a iioat, operable by the Water in said tank, and means actuated by said float vwhen the water in said tank reaches anlnastructure of the class described, a con-' 'densing tank, means for admitting water to said g rtank aandr for `discharging waterjtherefrom, a "valve'for admitting steam to said tank, a valve n for A.venting air from said tank, a thermostat exn. the, tlovv` of vWater into the same.

Y c 2,107,889 with Water -in said tank, to openboth of said valves andwhen heated by steam in said tank toclose said valves.

4SQA` structure as described in claim 7 which :l als'ovincludes a oat member constructed and Vpositioned to close saidairlventingkvalve upon tending into said tank and having an element shifted to dierent positions when said element is heated and cooled, an electric circuit having a switch connected to said element, and electrically controlled devices in said circuit for actuating said valves to admit steam to said tank and tofvent air from said tank concurrently.

*10, A structure as described in claim 9 which also includes a oatl'member constructed and positioned to close said air venting valve upon the flow of water into the same.

' JOHN M. DOUGHERTY. 

